And still they come. Vols 59 and 60 in Naïve’s heroic complete Vivaldi Edition, now seemingly intent on the home straight, cover sacred and secular music for alto, the composer’s favourite voice type. Except for the Salve regina, the sacred works were fashioned for talented contraltos at the Pietà, where Vivaldi took over the duties of maestro di coro (for no extra fee) in 1713. It’s all too easy, of course, to take the Red Priest for granted. Yet even Vivaldi-sceptics might be struck by the expressive power of the music here, whether in the passionate motet for Tenebrae Filiae maestae Jerusalem, the mingled vigour and tenderness of the Salve regina or the motet Non in pratis, with its gravely beautiful central aria.

The French contralto Delphine Galou has long proved herself a fine Vivaldi stylist and sings here with her trademark imagination and involvement (blandness is not in her armoury). In captious mode I’d point to moments where her pure, rather instrumental timbre develops a flutter under pressure. At times her rhetorical intensity can compromise evenness of line and tone. But Galou’s singing always compels with its eloquence of phrase and urgent engagement with the text. The tenor Alessandro Giangrande makes a lively duet partner in the hymn Deus tuorum militum – determinedly jolly, despite its text. He is, though, less convincing slipping between falsetto and his natural tenor voice in the fragmentary antiphon Regina coeli, written for a Pietà contralto with a freakishly low range. Dantone’s Accademia Bizantina provide colourful, vividly gestural accompaniments, and with the brilliant Alessandro Tampieri relish the fantasy and flamboyance of the D major Violin Concerto with double orchestra.

Galou and Accademia Bizantina are likewise in their element in the disc of cantatas and opera arias. Most familiar here is the Arcadian chamber cantata Cessate, omai cessate, long a countertenor favourite but also recorded by a handful of contraltos, including Sara Mingardo (Opus 111, 11/97). If Mingardo sings with more rounded depth of tone, Galou’s no-holds-barred passion and anguish are just as affecting, not least in the terrific final ‘vengeance’ aria. She finds a bright, sopranoish edge for the cheerful O mie porpore più belle, composed to celebrate the new Bishop of Mantua, and brings a virtuoso swagger to the horn-fuelled homage cantata Qual in pioggia dorata, music to massage a princely ego. Although the booklet note is light on dramatic context (depressingly familiar litany), Galou characterises each of the assorted opera arias with flair. My own highlights included the gentle pathos of ‘Andrò fida’ from Tito Manlio, soft-toned recorders cooing in sympathy with the voice, and Damira’s gleefully manipulative ‘Semplice non temer’, tossed off with real comic panache. Minor reservations aside, both discs are worthy of the consistently high standards set by the whole series. Galou fans and Vivaldi collectors alike should need no encouragement.